(a) Field of the Invention
The present invention relates to a display device and a driving method thereof, and more particularly, to a display device capable of reducing power consumption and preventing a luminance change and a driving method thereof.
(b) Description of the Related Art
Currently, display devices are required for devices such as computer monitors, televisions, mobile phones, and the like, all of which are widely used. The display devices include cathode ray tube display devices, liquid crystal displays, plasma display devices, and the like.
Display devices include a graphic processing unit (GPU), a display panel, and a signal controller. The graphic processing unit transmits the image data for each screen to be displayed on the display panel to the signal controller. The signal controller generates a control signal for driving the display panel and transmits the control signal together with the image data to the display panel, thereby driving the display device.
Images displayed on the display panel are largely classified into still images and moving or motion pictures. The display panel displays several frames per second and in this case, if the image data included in each frame are the same as each other, the still image is displayed. Further, if the image data included in each frame are different from each other, the motion picture is displayed.
Because the signal controller receives the same image data from the graphic processing unit for every frame, even when the display panel displays a still image instead of a motion picture, the power consumption is increased.
Recently, many attempts have been made to reduce the power consumption of display devices. In one proposed method, the image data of the still image is stored in a frame memory by adding the frame memory in the signal controller and the stored image data is provided to the display panel while displaying the still image. Such method is referred to as a Panel Self Refresh (PSR) mode, and because the image data does not need to be received from the graphic processing unit while displaying the still image, the graphic processing unit is inactivated, thereby reducing the power consumption.
However, when a display device is being driven in the PSR mode, there is a problem in that the power consumption increases according to the addition of the frame memory.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.